<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
</head>

<body>
<input id="btn1" type="button" value="按钮" />
<script>
var oBtn=document.getElementById('btn1');

oBtn.onclick=function ()		//匿名函数
{
	alert('a');
};
</script>
</body>
</html>
